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Multi-Spacecraft Observations of SEPs: Applications for 3D Propagation Modelling. B. Klecker Max-Planck-Institut für extraterrestrische Physik, 85740 Garching, Germany W. Dröge University of Würzburg, Würzburg, Germany Y.Y. Kartavykh, A. Kovaltsov
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Multi-Spacecraft Observations of SEPs: Applications for 3D Propagation Modelling B. Klecker Max-Planck-Institut für extraterrestrische Physik, 85740 Garching, Germany W. Dröge University of Würzburg, Würzburg, Germany Y.Y. Kartavykh, A. Kovaltsov Ioffe Physical-Technical Institute, St. Petersburg, Russia STEREO SWG #20 Meredith, NH October 27 - 29, 2009
OUTLINE • Part 1 3D Propagation Model and First Results • Part 2 Future Applications to Observations with STEREO-A/B, SOHO, ACE, WIND Activity started as part of the ISSI Team # 118 on Transport of Energetic Particles in the Inner Heliosphere Team Members: M. Desai, W. Dröge (Lead), P. Evenson, B. Heber, T. Horbury, Y.Y. Kartavykh, B. Klecker, K.-L. Klein, S. Krucker, R. Schlickeiser, C. Smith
THE 3D PROPAGATION MODEL Particle propagation in a 3D archimedian spiral magnetic field, Including the effects of • pitch angle scattering, • focusing, • diffusion perpendicular to B • convection and adiabatic deceleration Presently: model assumes impulsive injection at a localized source at the Sun Numerical Method, solving stochastic differential equations (Paper “Anisotropic three-dimensional focused transport of solar energetic • particles in the inner heliosphere“ by Dröge et al., ApJ, in refereeing process)
THE 3D PROPAGATION MODELSimulation for 4 MeV Protons r= 0.3 AU p=0. 01 4h Path of 4 MeV p with and without perpendicular diffusion Dröge et al., 2009 12h
THE 3D PROPAGATION MODEL More realistic: perp scales with gyroradius: = 0.01
THE 3D PROPAGATION MODEL Single Spacecraft Applications DROPOUTS CUTOFFS Mazur et al. (2000) ACE ULEIS 1 May 2000 • no velocity dispersion • time variations correspond to large spatial gradients perpendicular to B, convected past the spacecraft
APPLICATION OF 3D PROPAGATION MODEL Single Spacecraft Observations Intensity-Time Profiles No Perp Diffusion Perp diffusion 100 Intensity 10-1 10-2 With corotation Cutoff ULEIS / ACE Kartavykh, et al., 2007 Dröge et al., 2009 upper limit forperp / ||: < 10-4(at 1 AU)
APPLICATION OF 3D PROPAGATION MODELSingle Spacecraft Observations Anisotropies • 2 1 Case 2: Small anisotropy S/C entering flux tube filled with particles later Case 1: Large anisotropy S/C inside flux tube filled with particles
APPLICATION OF 3D-PROPAGATION CODE TO OBSERVATIONS BY STEREO-A/B, ACE, WIND, SOHO Multi Spacecraft Observations • Use remote observations to obtain injection parameters at the Sun Type II, III bursts, X-rays, CME- Radio - observations, ... • In-situ Observations Use Intensity-Time Profiles, Anisotropy-Time Profiles as measured on several spacecraft separated in longitude, latitude, radial distance to infer • Injection characteristics at the Sun • Propagation parameters in Interplanetary Space
APPLICATION OF 3D-PROPAGATION CODE TO OBSERVATIONS BY STEREO-A/B, ACE, WIND, SOHO Candidate Time Periods May 2007 Nov 2008 May 2009 3 A - B Separation: 9.2° (http://www2.physik.uni-kiel.de/stereo/browseplots/index.php)
2008 - Nov 3/4 EventsIn-SituObservation with ACE and STEREO Candidate Time Periods May 2007 Nov 2008 May 2009 (II) Nov 3/4 2008 Event N35W38 C1 X-ray event Type III burst Small CME (Wiedenbeck et al., ICRC 2009; Mason, et al., ApJ 2009) Wiedenbeck et al., 2009
ORBIT CONFIGURATION OF STEREO-A/B and ACE for Day 309 (Nov 4) 2008 Event: N35W38 Separation Footpoint - Flare STEREO-B -2° ACE 24° STEREO-A 45° A - B Separation: 82° Configuration of STEREO / ACE for Day 309 (Nov 4), 2008 (http://www2.physik.uni-kiel.de/stereo/browseplots/index.php)
2008 - Nov 3/4 EventsRemote Observation with SOHO and STEREO SOHO STEREO-B STEREO-A Nov 4, 2008 Event Active Region 11007
2008 - Nov 3/4 EventsRemoteObservation with STEREO and WIND STEREO / WAVES WIND / WAVES Nov 3 Onset times on Nov 3, 22:45 Nov 4, 03:24 Nov 4
2008 - Nov 3/4 EventsRemoteObservation with SOHO SOHO / EIT CMEs Nov 3 23:30 Nov 4 03:54 Speed: ~ 370 km/s ~ 732 km/s Width: ~ 46° ~ 66°
2008 - Nov 3/4 EventsIn-SituObservation with ACE and STEREO Candidate Time Periods May 2007 Nov 2008 May 2009 (II) Nov 3/4 2008 Event N35W38 C1 X-ray event Type III burst Small CME (Wiedenbeck et al., ICRC 2009; Mason, et al., ApJ 2009)
2008 - Nov 3/4 EventsIn-SituObservation with ACE, WIND and STEREO ACE / EPAM WIND / 3DP Type III bursts on Nov 4: 03:24
2008 - Nov 3/4 EventsIn-SituObservation with ACE, WIND and STEREO STEREO / SEPT STEREO / SEPT
POSSIBLE COMPLICATIONSFlare Longitude is not Necessarily Injection Longitude Intensity contours of 50%max type III bursts Magnetogram Open field line maps computed with PFSS model Fast access to open field lines at large due to non-radial flux tubes Klein, et al., 2008
2008 - Nov 3/4 EventsEvent Summary • ~40 - 300 keV electrons observed over large range of solar longitudes • intensity (two injections)- and anisotropy-time profiles are providing constraints on pitch angle scattering, perpendicular diffusion, and location of injection • PFSS model does not show open field lines that connect to near-equator region • Possible resolution of this puzzle: dynamical changes in magnetic field configuration by CME Mason, et al., 2009 Open field line maps from photosphere to 2.5 RS surface from PFSS model . Yellow: open field lines that connect to the ecliptic
SUMMARY May 2007 Events Good candidates for single spacecraft analysis of intensity and anisotropy Nov 2008 Events Multispacecraft analysis could be promising, Ion intensity too small May 2009 Events Good statistics for ions and electrons, intensity and anisotropy measurements are available Events observed at large longitudinal separation: non-radial flux tubes close to the Sun may be important